The Northern Pacific Railroad Completion Site is the location of the golden spike ceremony for the completion of the Northern Pacific Railway (NP) in 1883. The site is located near Gold Creek in Powell County, Montana off of Interstate 90, approximately 59 miles (95 km) southeast of Missoula and 40 miles (64 km) west of Helena.

The Northern Pacific Railway was a transcontinental railroad that operated across the northern tier of the western United States, from Minnesota to the Pacific Northwest. It was approved by Congress in 1864 and given nearly 40 million acres of land grants, which it used to raise money in Europe for construction.